The present invention relates to an improved construction of cable connection with slack cable-brake release at an aerial cableway wherein a traction cable and possibly a counter cable are secured to the travelling mechanism or carriage of the aerial cableway and the brake mechanism of the aerial cableway is automatically released by a brake release mechanism influenced by the tension or traction of the cable upon decrease of the cable traction to a predetermined minimum value.
The most important attachment means for wire cables are cast cable sleeves, collars, clamps and cable grommets of the most different constructions. These attachment means are also used at aerial cableways for connecting the tensioned or traction cable and counter cable to the travelling mechanism or carriage. In order to ensure for a satisfactory operational reliability, it is necessary that the aerial cableway be equipped with catch brakes which automatically and immediately are released when the cable traction or tension drops to a minimum value and especially upon disappearance of the tension in the cable owing to rupture of the cable. Simple, robust and positive means for determining the cable tension or traction are measurement springs (spring sets or packages) by means of which the cable traction can be converted into a proportional spring displacement. For the catch brakes there then can be provided brake release mechanisms which contain such measurement springs, wherein the spring displacement directly or indirectly determines the release criterium.
In the case of aerial cableways there is thus usually connected the traction cable and, if present, also the counter cable, while intermediately interposing a brake release mechanism containing a measuring spring arrangement, with one of the aforementioned attachement means at the travelling mechanism. The cable attachment (collars, clamps, grommets) and the measuring spring arrangement in this case accommodates the entire cable traction and must be appropriately dimensioned. The required dimensioning does not, however, have associated therewith any difficulties and also does not lead to increased costs. Additionally, there is to be characterized as advantageous the simple construction and small spatial requirements of this known cable connection with slack cablebrake release. However, these advantages are also counteracted by certain disadvantages, and specifically with regard to the cable attachment as well as the brake release. For the operational reliability the tension strength of the cable connection location is decisive. It is just the cable connection which, however, is markedly loaded mechanically and owing to the manipulations which occur for the attachment at the tension or traction cable such is rather sensitive to the influences of the surroundings. Thus, for instance, the cable, due to the continually present oscillations of the cable at the connection locations owing to the forced oscillations of the considerable collar mass due to the full load is subjected to bending loads, and the frequent temperature changes, water, ice and industrial waste gases easily lead to the formation of rust and changes in the structure of the material at the connection location, so that it is only possible to detect the presence of defects and faults from the surface properties of the connection location. Additionally, the expenditure in work is considerable as concerns shortening of the cable which is required at periodic intervals. The same is more or less also true for the measurement spring arrangement. The adjustment of the measurement springs, which are markedly dimensioned owing to the full load, to the release criterium is difficult and inaccurate and furthermore, pronounced cable oscillations can bring about erroneous release operations. Such heretofore known fully loaded cable connections with slack cable-brake release are accordingly associated with a certain unreliability which becomes greater with increasing load and in the case of fully-loaded cable installations leads to risks in safety.